x=20
y=10
x=x+y
print(x)
x+=y
x-=y
print(x)
x*=y
print(x)
x/=y
print(x)
print(type(x))
x%=2
print(x)
z=3
y//=z
print(y)

y**=2
print(y)

a=b=c=100
print(a,b,c)

a,b=10,20
print(a,b)

print('-----如何交换两个变量的值呢？-----')
a,b=b,a
print(a,b)

a=10
b=20
c=30
a,b,c=b,c,a
print(a,b,c)